European Journal of Criminology
2008; 5; 99 European Journal of Criminology
Andrew Silke Radicalization
Holy Warriors: Exploring the Psychological Processes of Jihadi
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Los Angeles, London, New Delhi and Singapore
Exploring the Psychological Processes of Jihadi
University of East London, UK
This paper aims to provide an overview of the psychology of individuals who join
and engage in terrorism, and in particular of individuals who engage in jihadi-
motivated terrorism such as that carried out by al-Qaeda and its affiliates. Based on
the most reliable available evidence, this paper gives an account of the psychology
and motivations of such individuals and the processes that facilitate and develop
Jihadi Extremism / Radicalization / Terrorism.
On 7 July 2005 the first Islamist suicide bombings in Europe were carried out
in the UK. Four suicide bombers (three of whom were British born) detonated
bombs in London during the morning rush hour; 52 people were killed by the
bombers and more than 700 people were maimed and injured. Exactly two
weeks later, on 21 July, more extremists attempted to carry out a second wave
of suicide attacks on London’s transport system but this time the devices
failed to detonate and no one was killed.
Following in the wake of even more devastating attacks in Madrid in
2004, these events highlighted the severity of the threat now facing Europe
from jihadi terrorists motivated by a radical interpretation of Islam. The fact
that a growing number of the terrorists were home grown has represented a
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disturbing development and left the authorities and others struggling to
understand the radicalization process that can produce such extremists within
the relatively stable and prosperous states of Western Europe.
The first hurdle to be cleared in any effort for understanding is to clar-
ify what exactly is meant by ‘terrorism’. The questions of what constitutes
terrorism and who is a terrorist are deeply problematic. There is still no pre-
cise and agreed definition of terrorism, and some writers have concluded that
‘it is unlikely that any definition will ever be generally agreed upon’ (Shafritz
et al. 1991: 260). In this article, however, I follow the concise definition pro-
vided by Crenshaw (1992: 71), who described terrorism as ‘a particular style
of political violence, involving attacks on a small number of victims in order
to influence a wider audience’. The claims as to what behaviours fit this def-
inition still vary considerably, but the focus of this article is very much on
‘insurgent’ terrorism, which is essentially a strategy of the weak, adopted ‘by
groups with little numerical, physical or direct political power in order to
effect political or social change’ (Friedland 1992: 82).
In practical terms, ‘insurgent’ terrorists are members of small covert
groups engaged in an organized campaign of violence. This violence is often
extreme and frequently indiscriminate. The terrorists themselves tend to live
isolated and stressful lives and enjoy varying levels of wider support. In the
past, groups that fit within this framework have included the Irish
Republican Army (IRA), the Basque separatist group ETA, the Red Army
Faction and the Italian Red Brigades. In this article I primarily focus on
al-Qaeda and the jihadi extremists affiliated with it.
The word ‘jihad’ is often assumed to mean ‘holy war’ but the mean-
ing is more complex than that. The phrase derives from the Arabic for
‘struggle’, and within Islam there are two forms of jihad: the Greater Jihad
and the Lesser Jihad. The Greater Jihad refers to an individual’s personal
struggle to live a good and charitable life and adhere to God’s commands
as understood within Islam. This is a strictly personal and non-violent phe-
nomenon. The Lesser Jihad refers to violent struggle on behalf of Islam. The
jihadis then are literally ‘those who struggle’. This term is typically used to
describe individuals who have volunteered to fight in the Lesser Jihad, and
the expression is used by members of groups such as al-Qaeda to describe
themselves. (Mujahideen, meaning ‘holy warriors’, is another expression
commonly used to refer to Muslims engaged in the Lesser Jihad).
Quality of the research evidence
This article aims to provide an assessment of the psychological basis of
jihadi radicalization. A great deal has been written on this subject since the
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attacks of 11 September 2001 (9/11), and much has been claimed, but crit-
ical issues remain concerning the quality of the evidence being used to jus-
tify many claims (Ranstorp 2006; Chen et al. in press).
Most research looking at jihadi radicalization has been limited, often
relying on anecdotes and a small number of case studies (e.g. Mazarr 2004;
Nesser 2006). Even the best available research on this subject is almost all
based on secondary analysis of data, more specifically of archival records
(e.g. Sageman 2004; Bakker 2006). These, however, are traditional features
of research on terrorism where over 80 percent of all research is based
either solely or primarily on data gathered from books, journals, the media
(or media-derived databases) or other published documents (Silke 2001).
An old failing of the field has been the very heavy reliance on literature
review methods. Schmid and Jongman (1988) were very critical of the paucity
of fresh data that researchers were producing. In the 1990s, 68 percent of
the published research essentially took the form of a literature review and
did not add new information. Since 9/11, 65 percent of articles are still
essentially just reviews (Silke 2006). Research providing new information is
uncommon and where there is new information this is mostly gleaned in-
directly from reports in the media (e.g. Pape 2005).
Currently, only about 20 percent of research articles provide substan-
tially new knowledge that was previously unavailable to the field. The field
thus is top heavy with what are referred to as pre-experimental research
designs. Unfortunately, these are ‘the weakest designs since the sources of
internal and external validity are not controlled for. The risk of error in
drawing causal inferences from preexperimental designs is extremely high
and they are primarily useful as a basis . . . for exploratory research’
(Frankfort-Nachmias and Nachmias 1996: 147). For example, in only
1 percent of research reports have systematic interviews been used to provide
data and to date no such interview study has been carried out with jihadis.
The limitations of available research can be illustrated by reviewing
two of the key studies so far published on jihadi extremism. Sageman (2004)
studied 172 individuals who were or are members of extremist Islamist or-
ganizations. The data came from publicly available sources, mainly media
reports and transcripts of court proceedings. These sources are not always
reliable, and the study also suffers from the lack of a comparison with indi-
viduals who are not members of extremist groups. Nevertheless, the research
still provides a useful analysis of the backgrounds of extreme Islamists, and
many of the findings are very relevant to this paper. For example, the study
provided a detailed description of the profiles of jihadis with respect to
education, family background, childhood, socioeconomic background, re-
ligiosity, professions, and so forth. Sageman also explored the process of
recruitment into the jihad, and the lives of the 172 revealed that a surprisingly
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large proportion joined in small groups (and not as isolated individuals).
Even bearing in mind the acknowledged weaknesses, this study represented
a major step forward in social science research on al-Qaeda and jihadi
extremism, and was a significant improvement on the much more journal-
istic accounts that had largely dominated (e.g. Gunaratna 2002; Burke
2004; Vidino 2006).
A second significant study is the one by Bakker (2006), which in many
respects is essentially a replication of the earlier study by Sageman (2004).
It has a narrower focus in that it considers only jihadis active in Europe, but
the data set is larger than Sageman’s, with information on 242 individuals
who had been involved in jihadi terrorist attacks and attempts. As did
Sageman, Bakker relied on open source data for this study, again using
court and media reports.
Currently, there is no published research where the researchers have
had direct access to the jihadis. The result is that all of the analysis is done
at a distance. This means either relying on media or court reports, as Sageman
and Bakker have done, or else drawing inferences from other populations
that are believed to be relevant in some way to the jihadis. For example,
Ansari et al. (2006) distributed attitudinal questionnaires to 80 practising
Muslims in the UK. The questionnaires contained Likert-type measures of
attitudes towards religious martyrdom, terrorism, violence, suicide, jihad
and 9/11. In-depth interviews were also carried out with 13 respondents.
This research found that social identity had a major impact on attitudes:
respondents who felt their primary identity was Muslim held more positive
views towards jihad and martyrdom, whereas respondents with a dominant
British identity did not. Such studies are helpful in highlighting the key role
identity plays, but the work is limited because of the small sample size and
the fact that the respondents were not actually jihadis. Nevertheless, even the
pool of studies like this is currently very limited.
A different research strategy is to draw upon information about other
terrorist groups that are thought to be similar or to generalize about new
forms of terrorism. There is an increasing trend for commentators to argue
that we are currently experiencing an age of New Terrorism (e.g. Laqueur
2000; Kegley 2002). This thesis argues that terrorism today is significantly
different from terrorism in the past, primarily because it is now more lethal,
more violent and more heavily motivated by fundamentalist religion.
Al-Qaeda and its affiliates are held up as a good example of this new type
of terrorist group. Implicit in the thesis is an assumption that any under-
standing gained from an analysis of the Old Terrorism is not very relevant
to the understanding of the new form.
However, the New Terrorism thesis is overemphasized. At heart, the
argument often shows a poor awareness of the history of terrorism and
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overlooks the many examples of lethal, violent and fundamentalist terror-
ist groups of the past. For example, the Muslim Moros campaign of suicide
terrorism against US forces in the Philippines at the start of the 20th century
closely mirrors many of the problems faced by the Americans in Iraq at the
start of the 21st century (Woolman 2002).
Further undermining the idea that the New Terrorists are a breed apart
are the reports from researchers who have been able to interview terrorists
from many different groups and who have found more similarities than dif-
ferences between the different factions (e.g. Horgan 2005). Ultimately,
although context matters, this does not mean that research focused on the
IRA, for example, is not relevant for understanding the experience of other
terrorist groups, and vice versa. However, the New Terrorism thesis biases
our understanding of terrorism. It encourages the belief that terrorism today
is essentially a new phenomenon and that new ways of thinking are needed
to understand it. Post (1990: 29) noted that every ‘terrorist group is unique
and must be studied in the context of its own . . . culture and history’.
Although this is true, it is also the case that terrorist groups often have a
great deal in common and terrorist campaigns often follow similar patterns.
It would be wasteful to ignore entirely the insights and lessons from studies
of other groups and conflicts (Silke 2003).
The psychology of terrorism
When confronted with atrocities such as the Madrid and London bomb-
ings, it can be very difficult to consider the perpetrators as rational and
mentally healthy individuals. On the contrary, it is much easier to view
them as highly deviant personalities who are very likely to suffer from men-
tal illness and psychopathological disorders. Indeed, it is not just the gen-
eral public who feel this way. Many researchers on terrorism have shared
this view, and some have argued that terrorist groups are made up of a mix
of individuals suffering from psychopathic and paranoid personality dis-
orders (e.g. Post 1986; Pearlstein 1991; DeMause 2002). Such views have
had a powerful impact on government policy decisions.
As social science grapples to improve our current understanding of
terrorism, much of the research it is drawing on was originally aimed at
explaining how and why people were able to commit atrocities in past ages.
For example, after the end of the Second World War a number of surviving
Nazis, including Hermann Goering and Rudolf Hess, were tried for war
crimes at Nuremberg. Prior to the trials, 16 of these Nazi leaders were
assessed by an Allied psychologist. The psychologist concluded that their
scores were those of violent, power-hungry personalities, obsessed with
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death and lacking in any real human feeling. This was pretty much what the
world expected from the men responsible for the horror of the Holocaust.
Years later, however, the same Nazi scores were inserted among a selection
of scores from a group of average Americans. This mix was given to a panel
of experts who failed entirely to identify anything unusual about the Nazi
leaders, and instead concluded that all of the scores reflected stable and
healthy personalities (Harrower 1976).
What had happened with the Nazis is an example of attribution the-
ory. Attribution theory has shown that we tend to view our own behaviour
as stemming from situational or environmental forces, but that we see the
behaviour of other people as stemming from internal forces, such as their
personality (Quattrone 1982). If people are involved in extreme and violent
acts, we tend to assume that their personality must be similarly extreme and
deviant. We then tend to make any available evidence fit in with our as-
sumptions. This is exactly what happened with the captured Nazis, and the
same effect can be seen in the way most people consider the psychology of
Why does someone become a terrorist? The first answer offered to this
question was to suggest that (like the Nazi leaders) terrorists must be psy-
chologically different from everyone else. Their abnormality accounts for
their involvement in terrorism. This view was very popular in the 1970s and
it has survived in some form or other since then. As evidenced only too force-
fully on 11 September 2001, terrorist violence can often be extreme, and
extreme violence has a special ability to provoke extreme views about the per-
petrator. Despite the indiscriminate and extreme violence of many terrorist
attacks, the vast majority of research on terrorists has concluded that the per-
petrators are not psychologically abnormal (Silke 2003; Horgan 2005).
On the contrary, many studies have found that terrorists are psychologically
much healthier and far more stable than other violent criminals (e.g. Lyons
and Harbinson 1986). An act of extreme violence does not in itself show that
the perpetrator is psychologically distinct from the rest of humanity. Although
a few psychologists believe terrorists are mentally abnormal, their con-
clusions are based on very weak evidence (Silke 1998 provides a review of
this literature). Psychologists who have met terrorists face to face have nearly
always concluded that these people were in no way abnormal, and on the
contrary that they had stable and rational personalities.
This is not to say that people suffering from psychological disorders are
never found in terrorist groups. They are, but these are the exception and not
the rule. Quite simply, such people do not make good terrorists. They lack the
discipline, rationality, self-control and mental stamina needed if terrorists are
to survive for any length of time (see Taylor 1988). When they are found, they
tend to be fringe members of the group and not central characters.
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Overall, terrorists are a very heterogeneous group and the range of
people who become involved in terrorism is vast. They can vary hugely in
terms of education, family background, age, gender, intelligence, economic
class, and so on. Consequently, the manner in which they became a terror-
ist can also vary, and factors that played a pivotal role in one person’s deci-
sion to engage in terrorist violence may play a peripheral role in the
decision-making of others, or indeed may have played no part at all.
Despite this heterogeneity, four decades of research have shown that
a number of factors appear to be relatively common in the background of
terrorists (Silke 2003). Becoming a terrorist is for most people a gradual
process (Horgan 2005), and progressing through the different stages is usu-
ally not something that happens quickly or easily. However, considering the
factors in the following sections will help in gaining understanding and
insight into this process. Not all of these factors will necessarily be present
in the experience of every terrorist, but most will be there at least to some
degree. Neither are their boundaries exclusive. They interact and mesh
together in a complex manner that can often be very difficult to disen-
tangle or differentiate in the case of any one person. Ultimately, it is the
combined impact of a number of factors that pushes and pulls someone into
becoming a terrorist, and these factors will vary depending on the culture,
the social context, the terrorist group and the individual involved.
Age and gender
As yet, there is no scientific evidence of any genetic role in determining why
certain people become involved in terrorism, and specific biological ap-
proaches to explaining terrorism have tended to be very flawed (see Silke
The most important biological factors associated with joining a ter-
rorist group are age and gender. Although a causative role for these factors
is not entirely unambiguous, there is certainly a correlation between these
two factors and most recruits to terrorist organizations. Ultimately, most
people who join a terrorist group are young – by young here I am referring
to teenagers and people in their early twenties. Further, most recruits to ter-
rorist groups are male.
It is already well established in other spheres that young males are
associated with a multitude of dangerous and high-risk activities (Farrington
2003). Statistics on violent crime consistently show that perpetrators are
most likely to be males between 15 and 25 years of age (e.g. Budd et al.
2005). This is a very robust finding that is remarkably stable across cultures
and regions (e.g. Schönteich 1999). More crime in general is committed by
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teenagers and young adults than by any other age category. Adolescence
brings with it a dramatic increase in the number of people who are willing
to offend, and cross-cultural studies tend to show that the peak age for male
offending has generally been between 15 and 18 years of age, falling off
quickly for most individuals as they grow older (Farrington 2003).
Research studies have found that between 54 percent and 96 percent of
young men have been involved in some form of delinquent behaviour, with
good international agreement on this finding (e.g. Fox and Zawitz 2006).
Consider for example the research by Junger-Tas (1994), who compared
delinquency rates in five countries and found that 64–90 percent of all young
men surveyed admitted to having committed a criminal offence (with around
45 percent having committed at least one offence in the previous 12 months).
These rates are far higher than those for other age groups. As Moffitt (1993:
675) noted, ‘actual rates of illegal behaviour soar so high during adolescence
that participation in delinquency appears to be a normal part of teen life’.
There is also widespread agreement that young men are more heavily
involved in crime than are young women, in terms of both the quantity and
the severity of the offences. Studies on violent crime for example show that
the ratio of male to female offenders varies by at least 2:1 to 4:1 in western
cultures, with this ratio generally climbing higher the more serious the
offences become (e.g. Rutter et al. 1998).
Explaining why young men are so inclined to get involved in deviant
behaviour is not straightforward. There has been a great deal of research on
juvenile delinquency, but most of this has focused on examining life-course
persistent offenders – the small minority of adolescents who continue to
offend at significant levels into their adult life (Hollin et al. 2002). These
individuals normally comprise no more than 4–7 percent of all juvenile
offenders and a range of factors have been found to predict these persistent
offenders (such as family criminality, poor school performance, family
poverty, poor housing and high impulsivity). Yet, in focusing so much atten-
tion on life-course persistent offenders, surprisingly little effort has been
devoted to the majority who cease deviant activity in their twenties.
Nevertheless, there is widespread recognition that most young men get
involved in some form of criminal activity and deviancy during their teenage
years. This involvement tapers off dramatically as individuals get older,
having all but vanished for most by the time they reach 28. With terrorism,
the same factors that attract young men to deviant activity in other spheres
can also play at least a partial role in the attraction terrorism holds for a few.
Higher impulsivity, higher confidence, greater attraction to risk-taking and
a need for status can all work to give life as a terrorist a certain appeal for
some young males. As discussed later, a desire for revenge and retribution is
an extremely common motive for joining terrorist groups and again research
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indicates that young men hold the most positive attitudes toward vengeance
and are the ones most likely to exhibit and approve of vengeful behaviour
(Stuckless and Goranson 1992; Cota-McKinley et al. 2001).
Although young men make up the majority of terrorist recruits, some
recruits are female and a few are much older. Out of 242 jihadi terrorists
identified by Bakker (2006) in his review of jihadi terrorism in Europe since
2001, 5 were women. The review found a relatively wide age range, stretch-
ing from 16 to 59 at the time of their arrests, but most of the jihadis were
in their teens to mid-twenties (Bakker 2006).
Further, it is also very evident that, even in troubled regions such as
Northern Ireland, the vast majority of young males living in the affected
communities do not in fact become terrorists. The unavoidable conclusion
then is that other factors besides age and gender must be playing crucial
roles in the process and decision to become a terrorist.
Education, career and marriage
In considering the factors associated with violent radicalization, especially
towards jihadism, it is worth focusing on some surprising findings.
Traditionally, factors such as good educational achievement, good socio-
economic background and marriage have been associated with a reduced
likelihood of criminal offending. An analysis of the backgrounds of jihadis,
however, suggests that such trends do not apply as strongly to them.
Sageman’s (2004) survey of members of extremist Islamist groups found
that they generally tend to be well educated as a group. Over 60 percent had
some higher or further-level education. Such findings undermine the view
that Islamic extremism can be explained as a result of ignorance or lack of
education. Similarly, Sageman (2004) found that about three-quarters of
Islamist extremists came from upper- or middle-class backgrounds. A rela-
tively small proportion (27 percent) came from working-class or poor back-
grounds. Poorer individuals accounted for a larger proportion of Bakker’s
(2006) sample, but there was still a very large middle-class element. This
undermines explanations for involvement in extremism resulting from per-
sonal poverty or deprivation. Further, at the time of joining, the majority of
Islamists had professional occupations (e.g. physicians, teachers) or semi-
skilled employment (e.g. police, civil service, students). Less than a quarter
were unemployed or working in unskilled jobs.
Finally, Sageman (2004) found that 73 percent of members were married,
and that most of these men had children. Bakker (2006) also found relatively
high levels of marriage among jihadis. Family commitments have clearly
not prevented individuals from embracing jihad.
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It is often assumed that getting married and settling down is a signifi-
cant factor in explaining desistance from crime in general. There is some
research support for this view, but research findings show that the relation-
ship is not entirely straightforward (Farrington and West 1995). Some crim-
inological research has highlighted that marriage at a young age either can
have no impact in terms of diminishing offending behaviour, or else can be
associated with an increase in criminality. The quality of the relationship, for
example, as opposed to the fact that it exists has been found to be a crucial
factor. West (1982) found that marriage had no effect among very young
adults and that a preventive effect occurred only among older adults. Ouimet
and LeBlanc (1993) found that cohabitation with a partner is positively asso-
ciated with crime among very young adults (18–23 years old). In this study,
marriage was found to contribute to desistance only after the age of 24.
Ouimet and LeBlanc explained the negative impact of an early marriage or
cohabitation in terms of seeing it as a possible sign of impulsiveness and that
marriage at such young ages could lead to significant economic difficulties
and family discord.
Building on such findings, Sampson et al. (2006) argued that marriage
becomes a positive influence for desistance only once the relationship meets
certain quality criteria. Strong social relationships need time and effort to
develop. As a result, a marriage or other significant relationship cannot be
expected to exert its fullest impact until a sufficient amount of time has
passed. Laub and Sampson reviewed data from a series of longitudinal stud-
ies of criminal behaviour. The results showed that desistance from crime is
facilitated by the development of quality marital bonds, and that this influence
is gradual and cumulative over time. On average, a five-year-old marriage
has more of an impact on desistance than a one-year-old marriage. Thus,
the timing and quality of marriage matter: early marriages characterized by
social cohesiveness lead to a growing preventive effect. Laub and Sampson
(2001) concluded that the effect of a good marriage takes time to appear,
and that the influence grows slowly until it inhibits crime.
In considering jihadi terrorism, a further important issue is whether
there are different marriage patterns within Muslim communities and the
possible impact of practices such as arranged marriages. Research on
jihadis has found very high levels of marriage among members of such
groups. For example, Sageman (2004) found that 70 percent of members of
groups such as al-Qaeda were married. This included many individuals who
carried out suicide attacks.
The UK’s 2001 census found that young British Muslims (16–24 year
olds) had the highest rates of marriage of all groups in the UK (National
Statistics Online 2007a): for example, 22 percent of Muslims in these age
ranges were married. (The Muslims were the third-lowest group to be
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co-habiting but not married; Sikhs, Hindus and Muslims were the groups
least likely to co-habit.) Christians and those with no religion were the least
likely to be married – just 3 percent of 16–24 year olds in each group.
Divorce rates among Muslims also appear to be low: 17 percent versus
34 percent for Christians and 43 percent of those with no religion. Thus the
high levels of marriage seen among jihadis may simply be a reflection of
wider cultural practices and, as a result, the relationships between marriage
and desistance from crime that have been observed for other groups may
not apply to Muslims. Further, Sageman (2004) highlighted that many
jihadi marriages are to wives who share strong ideological beliefs support-
ing jihadism (or that the wives’ families share such beliefs). Thus the mar-
riage provides an essentially endorsing environment for jihadist views as
opposed to a restraining influence.
Also of relevance is the importance of peers in facilitating radicaliza-
tion. Warr (1998) has argued that many of the benefits of marriage in
reducing illegal behaviour relate to its impact on peer interaction. He found
that marriage leads to a sharp decline in time spent with friends and hence
reduces exposure to delinquent peers. On this argument, marriage is an im-
portant influence in favour of desistance when it reduces, weakens and
severs ties with delinquent associates. In the case of married jihadis, this
effect does not occur and peer interactions remain substantial in the lives of
the extremists as they are radicalized.
The findings on education and economic background add to a grow-
ing body of research that has found that there is no clear link between
poverty or deprivation and membership of extremist organizations
(Maleckova 2005). The explanation proposed by Maleckova is that terror-
ists are motivated by belief in a political cause and not by economic factors.
Thus, factors associated with desistance among other types of criminal
offender (who often are motivated by economic factors) will have less of an
impact on political offenders. As summarized by Maleckova (2005: 41):
Just as political participation is much more typical of people who are wealthy
enough to concern themselves with more than mere economic subsistence while
the impoverished are less likely to vote, the poor are also less likely to become
engaged in terrorist organizations.
Identity has been shown to play a vital role in explaining involvement in ter-
rorism. Recruits always belong to the section of society that supports or shares
the aims, grievances and ambitions of the terrorist group. In the case of jihadi
extremism, individuals need to have a strong sense of Muslim identity and,
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equally, to identify strongly with the wider Muslim community – the umma.
Recruits consistently report that, prior to joining, they perceived they had a
very strong connection to other Muslims across the globe. This wider connec-
tion brought with it a sense of responsibility for these other Muslims, even
when the individual had never met them or travelled to their lands. Research
has shown that individuals who rate their Islamic identity as being more
important than their national or ethnic identity express more positive views on
topics such as jihad and martyrdom (Ansari et al. 2006). Further, the 2001
Home Office Citizenship Survey in the UK found that Muslims are more likely
than any other religious groupings to rate their faith as their primary identity,
and that this effect is particularly strong among young people aged 16–24
(Attwood et al. 2003).
The key aspects of social identity in the context of jihadism are (1) the
role of religion and (2) group loyalties.
The role of religion
Religion is assumed to lie at the heart of Islamist terrorism and, to a degree,
this is justified. As a movement, the global Salafi jihad has a strategic reli-
gious agenda with the ultimate goal of recreating past Muslim glory in a
great Islamist state stretching from Morocco to the Philippines, eliminating
present national boundaries. It preaches salafiyyah (from salaf, the Arabic
word for ‘ancient one’ and referring to the companions of the Prophet
Mohammed) – the restoration of authentic Islam – and advocates a strat-
egy of violent jihad, resulting in an explosion of terror to wipe out what it
regards as local political heresy. The global version of the movement advo-
cates the defeat of the western powers that prevent the establishment of a
true Islamist state (Sageman 2004).
Whereas the global jihad has a strategic religious aim, the religious
backgrounds of the people who join the jihad is not as clear-cut. Indeed,
Sageman (2004) found that only 18 percent of Islamist extremists have had
an Islamic religious primary or secondary education. In contrast, 82 percent
went to secular schools. These data undermine the view that Islamic extrem-
ism can be best viewed as resulting from brainwashing by teachers in
madrassas as part of normal primary or secondary education.
Sageman (2004) also found that 45 percent of Islamist extremists
were described by family and peers as being religiously devout as youth.
The majority, however, were not described as being religious as youth.
Further, 8 percent were raised as Christians and converted to Islam later in
life. There was a definite shift in the degree of devotion, however, prior to
joining: 99 percent of members were described as being very religious prior
to joining – this represents a major change from the situation when they
were younger. Sageman explained this change as originating from a desire
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for companionship, which was realized within the context of mosques. In
the West, many individuals were recruited at a time when they were living
away from their family home and old friends. Often the individuals were
living in a foreign land and were even more isolated from the society around
them. In the expatriate community from which most recruits come, espe-
cially in the West, the most available source of companionship with people
of similar background is the mosque. The mosque provides a setting for
non-radical individuals to socialize, but once groups form, in some cases
a process leading to increased religious devotion started. These findings sug-
gest that the mosque often provides the setting in which small groups
become radicalized but that this radicalization does not typically result
from the teachings of the official hierarchy within the mosque.
It is important to stress that not all Salafist Muslims support the
global jihad. Indeed, such individuals remain a minority among Salafists.
Thus, in order to understand the mind-set of Islamist terrorism, one needs
to move beyond the limits of religious doctrine and explore other driving
To a large extent, becoming involved in the jihad is a group phenomenon.
Individuals tend not to join the jihad as isolated individuals. Rather, it is
within small groups that individuals gradually become radicalized. This is
a trend identified by both Sageman (2004) and Bakker (2006). Usually,
members undergo a long period of intense social interaction with a small
group of friends, developing a strong mutual intimacy, which relieves their
In his analysis of 242 jihadis, Bakker (2006) found that these individ-
uals tended to become involved in terrorism through networks of friends or
relatives and that generally there were no formal ties with global Salafi net-
works. In short, the individuals were not becoming radicalized because of
the efforts of an al-Qaeda recruiter, but rather the process was occurring
almost independently of established jihadis.
Within the group context, individuals gradually adopt the beliefs and
faith of the group’s more extreme members (in a psychological process
known as ‘risky shift’). As both Sageman and Bakker found, individuals’ new
Salafi faith resulted in their becoming more isolated from older friends and
family, and led to an ever-increasing dependence on, and loyalty towards, the
group. With an increasing focus on this small group, their religious faith
became more important and more intense. The polarization experienced
within the group, combined with an increased sense of group identity and
commitment, helped to radicalize individuals and facilitate their entry into
the jihad in a way that was approved by their new social peers.
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Social marginalization appears to be a common factor in the backgrounds of
most jihadi recruits. Research has shown that most members of groups such
as al-Qaeda joined the jihad while they were living in a foreign country or
when they were otherwise isolated from older friends and family. Often these
individuals were expatriates – students, workers, refugees – living away from
home and family. Sageman (2004) found that 70 percent joined in a country
where they had not grown up; 8 percent were second generation and might
not have been fully embedded in their host country. In total, 78 percent of
the recruits had been cut off from their social and cultural origins, far from
family and friends.
If such marginalized groups are discriminated against or internal sections
believe that there is discrimination, then there will always be sections within
such communities who will be receptive to radical ideologies that advocate
changing or reforming the established, mainstream social system. The aim of
these changes will be to improve the lot of the disadvantaged group. People
on the margins have less to lose if the current social order is maintained and
conceivably a great deal to gain if it is radically changed. For example, a
number of factors have been identified as important elements in driving the
political conflict in Northern Ireland from 1969 and for increasing support
within Catholic communities for extremists (O’Leary 2007). In the context
of the Northern Irish conflict, these factors included:
• economic deprivation
• educational underperformance
• insufficient political representation
As a result, most Catholics in Northern Ireland had relatively little to gain by
supporting the status quo of Protestant-controlled government, which ran the
province until 1972, and potentially a great deal to gain if they could sub-
stantially reform or abolish that system of government. Among a disadvan-
taged Catholic population, ideologies advocating regime change would always
have some support and, in the face of continuing discrimination, ideologies
advocating even violent action to change the status quo attracted significant
support from some quarters.
In the context of jihadi extremism, it is currently clear that Muslim
populations in the West are experiencing considerable disadvantage. Indeed,
statistics suggest that the Muslim population within the UK is far more
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disadvantaged than Catholics were in Northern Ireland in 1969. Compared
with the UK population as a whole, Muslims have three times the unemploy-
ment rate; a higher proportion are unqualified; and a higher concentration
are living in deprived areas (National Statistics Online 2007b). Muslims are
significantly underperforming in secondary education and are also under-
represented in higher education: 36 percent of the population as a whole have
no qualifications, compared with 43 percent of Muslims.
In proportional terms, the number of UK politicians from Muslim back-
grounds is also out of balance. Approximately 3 percent of the UK population
is Muslim but they only have 0.3 percent of the country’s Members of
Parliament (MPs) and 0.9 percent of district councillors. For levels to be pro-
portionate, this would require 19 Muslim MPs (as opposed to the current 4)
and 675 district councillors (as opposed to the current 217).
This is a problem repeated in other European countries. There are
15 million Muslims in the European Union, reflecting approximately 3 percent
of the total population. However, Muslims hold only 0.8 percent of the seats
in the European Parliament: out of 785 representatives only 6 are Muslim.
Given such levels of disadvantage, it is not surprising that many
Muslim communities have come to view themselves as being unfairly mar-
ginalized. Other statistics, such as the fact that Muslims are grossly over-
represented in among prison populations, do not help (Joly 2005). The poor
performance of Muslims on these measures can be interpreted in different
ways – just as various interpretations of Catholic deprivation were offered
in the 1960s – but the imbalance certainly creates a sense of dissatisfaction
within the communities affected. Once a community and the individuals
within that community have been largely excluded from mainstream society,
they will lose much of their vested interest in maintaining that society.
If such deprivation is combined with exposure to an extremist ideol-
ogy that advocates reforming or even replacing the current order, then an
important step towards becoming an active extremist is taken. However,
although many people are politically committed to a variety of causes, few
are willing to commit acts of violence to further these ideals. To move into
terrorism still requires something more.
Catalyst events/perceived injustice
One of the most important elements in understanding the psychology of why
people become extremists is an appreciation of the psychology of vengeance.
It has long been recognized that for most terrorists a key motivation for join-
ing a terrorist organization ultimately revolves around a desire for revenge
(Schmid and Jongman 1988).
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Within the context of jihadi terrorism, the perception of a strong shared
identity and link with the wider Muslim world – the umma – has serious con-
sequences when the individual perceives that some Muslim communities are
being treated brutally or unfairly. Perceived injustices are important drivers of
individual decisions to become involved in militant activism. Catalyst events
(i.e. violent acts that are perceived to be unjust) provide a strong sense of out-
rage and a powerful psychological desire for revenge and retribution (Silke
2003). Importantly, one does not need to experience these unjust events first
hand in order to feel sufficiently motivated to become a terrorist. Indeed, the
events do not even have to involve friends or family members. Many terror-
ists report that they first joined the organization after witnessing events on
television or other media (e.g. O’Callaghan 1998). Although they did not
come from the area where the events occurred – or indeed even know the
people who lived there – at some level they identified with the victims. This
identification, combined with the perceived injustice of the event, can provide
a strong motivation to become involved in the jihad.
Such exposure is frequently facilitated through viewing extremist propa-
ganda. This propaganda may be extremely biased, but usually there is a basis
of truth and reality to the events portrayed. Islamist recruits tend to be exten-
sively exposed to such propaganda material, with graphic images of abuse
and violence being drawn from a wide range of conflicts involving Muslim
populations, including Kashmir, Chechnya, Bosnia and the Palestinian
Territories (Weimann 2006). US foreign policy is also heavily emphasized,
with recent propaganda focusing on the US invasion and occupation of
Afghanistan and Iraq. In a number of public statements (including the last
statements of suicide bombers) Islamists specifically draw attention to these
conflicts as a justification for their own violence.
Exposure to death-related imagery, such as that contained in the jihadi
propaganda, results in what psychologists refer to as a ‘mortality salience’
effect. A variety of research studies have shown that mortality salience gen-
erally increases identification with and pride in one’s country, religion, gen-
der, race, etc. (for a review see Pyszczynski et al. 2002). Crucially, mortality
salience can lead to an increase in support for extremism when it is linked to
group identity. For example, one study found that under mortality salience
conditions white Americans expressed more sympathy and support for other
Whites who expressed racist views. Similarly, Pyszczynski et al. (2006) found
that Muslim college students in the Middle East who were reminded of death
showed increased support for other students who voiced support for suicide
attacks. Significantly, the mortality salient group also indicated that they
would be more willing to take part in a suicide attack themselves.
One important element of the desire for vengeance is the surprising will-
ingness of individuals to sacrifice and suffer in order to carry out an act of
revenge. As Cota-McKinley et al. (2001: 343) comment, ‘vengeance can have
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many irrational and destructive consequences for the person seeking ven-
geance as well as for the target. The person seeking vengeance will often com-
promise his or her own integrity, social standing, and personal safety for the
sake of revenge.’ This observation is supported by a number of research stud-
ies (e.g. Fehr and Gachter 2002; Fowler 2005). In one Swiss study, researchers
gave students a cooperative task of the ‘prisoner’s dilemma’ kind: all students
in the study will benefit provided each behaves honourably, but those who
cheat will benefit more provided they are not caught (Tudge 2002). The stu-
dents were rewarded with real money if they did well and fined if they did not.
They were also able to punish fellow players who had cheated by imposing
fines, but could do this only by forfeiting money themselves. This meant that
those who punished others frequently would end up with considerably less
than those who punished others only a little. Participants tended to punish
cheats severely, even though they lost out by doing so. People seem to hate
cheats so much that they are prepared to incur significant losses themselves in
order to inflict punishment on the transgressors.
Cota-McKinley et al. (2001) show that revenge can fulfil a range of
goals, including righting perceived injustice, restoring the self-worth of the
vengeful individual and deterring future injustice. The vengeful individual
‘sends the message that harmful acts will not go unanswered’ (Kim and Smith
1993: 40). Not only is the goal to stop this particular form of maltreatment
in the future, it is to deter this transgressor from wanting to commit similar
crimes; additionally, vengeance may stop other potential offenders from com-
mitting similar crimes or from even considering similar crimes.
Significantly, some individuals are more vengeance prone than others.
Men hold more positive attitudes towards vengeance than women do, and
young people are much more prepared to act in a vengeful manner than are
older individuals (Cota-McKinley et al. 2001). It is not surprising then to
find that most recruits to terrorist groups are both young and male. In add-
ition, some evidence exists to suggest that religious belief also affects one’s
attitude to vengeance, with more secular individuals showing less approval
of vengeful attitudes (Greer et al. 2005).
Status and personal rewards
As well as providing an outlet for desires for vengeance, terrorist groups offer
other inducements and rewards to outsiders. There are considerable dangers
in becoming a terrorist. It can be an isolated, stressful and extremely dan-
gerous existence. Recruits to the IRA, for example, were warned that they
could expect only one of two things for certain from joining the organization:
a lengthy prison sentence or a violent death (e.g. Collins 1997; McGartland
1998). Hardship and suffering are seen as inseparable aspects of life as a
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terrorist, yet there are still often benefits and advantages to being in a terror-
ist group. For example, in many communities and societies, terrorist groups
and their members are regarded as courageous, honourable and important.
As one Palestinian terrorist described it, ‘[r]ecruits were treated with great
respect. A youngster who belonged to Hamas or Fatah was regarded more
highly than one who didn’t belong to a group, and got better treatment than
unaffiliated kids’ (Post and Denny 2002). It helps to remember that some
communities see members of these organizations or movements not as ‘ter-
rorists’ but rather as ‘freedom fighters’, ‘rebels’ or ‘the resistance’. One can-
not avoid the fact that applying the label ‘terrorist’ is often a value judgement
(and a negative one) and is often a label imposed from outside of the com-
munities and culture that the terrorists belong to. Those within that culture
can reject the term or else reject such a clumsy effort to describe the actors in
black and white terms. Ultimately, in many communities joining a terrorist
group increases the standing of a teenager or youth considerably. As another
Palestinian terrorist put it: ‘After recruitment, my social status was greatly en-
hanced. I got a lot of respect from my acquaintances, and from the young
people in my village’ (Post and Denny 2002).
As well as increased status and self-esteem, life as a terrorist offers poten-
tial recruits excitement and danger. Becoming a jihadi is a dangerous, high-risk
decision. Research has long shown that young males in particular are much
more attracted to high-risk behaviour than are other segments of the popula-
tion. The propaganda material developed by jihadi groups often attempts to
portray the jihadi lifestyle as an exciting, dangerous and meaningful one. In
recruitment videos seen by me, jihadis are shown training with a wide variety
of weapons, including assault rifles, machine guns, rockets and hand grenades.
There is also often footage of actual attacks against enemy targets.
Overall, such material paints a portrait of jihad as an exciting, dan-
gerous and rewarding activity. This may be an unrealistic portrayal, but it
will certainly have an appeal to some viewers. It is clear from other sources,
however, that danger and excitement are a feature of life as a terrorist. In-
deed, former terrorists, when asked what they miss about their old life as
active members, often talk about the closeness they felt with group mem-
bers, the sense of shared risk and common purpose. In their eyes, life as a
terrorist had an intensity and purpose that life outside of the organization
noticeably lacked. As a former IRA member described it:
A part of me missed being in the IRA. I had spent six years leading an action-packed
existence, living each day with the excitement of feeling I was playing a part in tak-
ing on the Orange State. At the very least, such activity gave a strange edge to my life:
I lived each day in a heightened state of alertness. Everything I did, however trivial,
could seem meaningful. Life outside the IRA could often feel terribly mundane …
I lived life with a weird intensity. I felt myself part of a large family whose members
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had powerful emotional links to each other. The idea of turning my back on the IRA
had become as repugnant to me as turning my back on my own children. As soon as
I left this intense environment I found myself missing my comrades: the dangers and
risks we shared brought us close. (Collins 1997: 158, 363)
A former Italian terrorist, when asked was there anything they missed
from their experience in a terrorist group, replied: ‘The fact of being totally
at risk’ (De Cataldo Neuburger and Valentini 1996: 137). It is important
then not to underestimate the appeal that this sense of risk and excitement
will exert on potential recruits, especially on those who are otherwise living
an ordinary but dull existence.
Opportunity and recruitment
People cannot become active terrorists unless they can find a terrorist group
that is willing to let them join. The individual – now located in the appro-
priate social grouping and motivated by a desire for retribution – needs to
identify an accessible avenue into a terrorist group. He or she is hampered
in this task because terrorist groups are nearly always illegal and member-
ship is a punishable crime. This presents difficulties for potential terrorists:
they must try to identify current members in order to facilitate entry into
the organization, yet they risk exposing themselves to the security services
if they approach the wrong person at the wrong time.
For ethnic terrorist groups such as Hamas or the IRA, the problem is
largely overcome by the use of legal political front organizations. Hamas, for
example, is a very large group and many elements of it are engaged in non-
violent legitimate activity. The organization openly runs and is associated
with many schools, hospitals, charities, businesses and mosques (Gunning
2007). For individuals interested in joining, it is not at all difficult to make
enquiries about doing so with people involved in the organization and for
them to be directed to the appropriate people. Similar situations exist else-
where, particularly in the case of nationalist and ethnic conflicts.
Some terrorist groups will accept almost any individual who asks to
join, but the vast majority of groups will closely vet all applicants. Other
groups will first arrange for applicants to carry out some minor illegal acts
to test their commitment. If the candidate carries these out successfully, then
he or she is formally accepted into the terrorist group.
For the individual who cannot identify a route into an established ter-
rorist group, or is refused membership after applying, the remaining options
are to form their own group or to wage a one-person terrorist campaign. For
example, the American far right’s concept of ‘leaderless resistance’ explicitly
endorses a philosophy of individuals (or small groups) mounting operationally
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independent campaigns of violence for ideologically similar reasons. The
concept was first pushed in books such as The Turner Diaries, but has now
been taken up and advocated very strongly on the Internet as well (Joyce-
Prior to 9/11, mosques played a key role in providing potential jihadis
with a route into groups such as al-Qaeda. Radical imams acted as a magnet
for potential recruits – for example, Omar Mahmoud Othman (alias abu
Qatada) and Mustafa Kamel (alias abu Hamza al-Mazri), who were active in
London. Indeed, a very high proportion of the UK’s Islamist extremists can
be linked by their attendance at one of two London mosques: Brixton mosque
and Finsbury Park mosque. At both national and international levels these
mosques established a reputation for hard-line extremist preaching that
advocated the use of violence for furthering the global Salafi jihad.
It is not always the case that a radical imam actively recruits potential
jihadis; rather, the social interactions between attendees listening to the ser-
mons at these mosques builds and reinforces ideological commitment. The
mosques offer opportunities for people to meet new friends and foster the
development of an ideological commitment to the jihad, and (critically) pro-
vide links to the jihad through already connected members. Finsbury Park
mosque was closed for an extended period following a major police raid on
20 January 2003. The police statement at the time of the raid stated that:
[The raid] was aimed specifically at individuals who have been supporting or
engaging in suspected terrorist activity from within the building. Police believe that
these premises have played a role in the recruitment of suspected terrorists and in
supporting their activity both here and abroad.
The preceding discussion has highlighted that Islamist terrorists do not fit
many of the stereotypes that shape public expectations. The individuals
involved do not suffer from mental illness or disorders, but instead are gen-
erally ordinary and unremarkable in psychological terms. Their involvement
in terrorism is usually the result of a gradual process – typically occurring
over a period of years. The sense of personal identity and social networks of
potential recruits are both extremely important factors. Most terrorists
become radicalized as members of a small group of like-minded individuals.
These groups do not start out as radical but become so gradually over time.
Sometimes the initial contacts are facilitated at mosques, but the relative isol-
ation of the individuals from the surrounding society beforehand appears to
play an important role in the early bonding of the group.
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As the members of a group become more interested in their faith, the
concern about abuses experienced by Muslims elsewhere becomes a more
prominent issue. Provocative and explicit propaganda can fuel these con-
cerns, though it is worth noting that both Muslims and non-Muslims in the
wider society can share many of these concerns.
Ultimately, ordinary psychological processes and small group dynamics
play a major role in understanding Islamist radicalization. It can be very dif-
ficult, however, to see beyond the common myths and assumptions that are
often offered as explanations for terrorist violence. Partly this is because the
process of involvement is, in many respects, at odds with our understanding
of the development and course of other types of offending. Farrington (2003:
224–5) summarized our existing understanding of other offenders:
The main risk factors for the early onset of offending before age 20 are well
known … individual factors (low intelligence, low school achievement, hyperactivity-
impulsiveness and risk-taking, antisocial child behavior, including aggression and
bullying), family factors (poor parental supervision, harsh discipline and child phys-
ical abuse, inconsistent discipline, a cold parental attitude and child neglect, low in-
volvement of parents with children, parental conflict, broken families, criminal
parents, delinquent siblings), socioeconomic factors (low family income, large fam-
ily size), peer factors (delinquent peers, peer rejection, and low popularity), school
factors (a high delinquency rate school) and neighbourhood factors (a high crime
Yet most of these factors are absent in the lives of jihadis, and indeed many
terrorists appear to come from backgrounds that would normally protect
against the onset of offending. This makes it clear that terrorists cannot
simply be regarded as typical criminals; on the contrary, they are a distinct
group, and in many ways the origins of their unconventional behaviour are
exceptional. This distinctiveness also helps to explain why many of the fac-
tors that are normally associated with desistance, such as marriage, edu-
cation and a career, often do not have the same influence on this group.
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Andrew Silke currently holds a Chair in Criminology at the University of East
London, where he is the Field Leader for Criminology and the Director for
Terrorism Studies. Professor Silke has a background in forensic psychology
and has worked both in academia and for government. He serves by invi-
tation on both the European Commission’s Expert Group on Violent
Radicalisation and the United Nations’ Roster of Terrorism Experts. His work
has taken him to Northern Ireland, the Middle East and Latin America.
Silke Psychological processes of jihadi radicalization 123
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